TABLE OF CONTENTS 



PAGE 



INTRODUCTION xi 



PART I 



I. OBJECT AND LINE OF ARGUMENT i 



II. THE OUTER BODY FORM ... 1 1 



III. THE APPENDAGES 26 



IV. THE MUSCULATURE 52 



V. THE NERVOUS SYSTEM 67 



VI. THE SENSORY ORGANS 84 



VII. THE ALIMENTARY CANAI 112 



VIII. THE CIRCULATORY SYSTEM 117 



IX. THE EXCRETORY AND OTHER GLANDS 124 



X. REPRODUCTION 140 



XI. DEVELOPMENT THE NAUPLIUS ... ... 148 



